Proposal would have imposed the nation's toughest restrictions on gun ownership.

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California Governor Jerry Brown has vetoed a bill that would have given California the nation's toughest restrictions on gun ownership.

California Gov. Jerry Brown vetoed a bill Friday that would have imposed the nation's toughest restrictions on gun ownership, saying it was too far-reaching.

The legislation would have banned future sales of most semi-automatic rifles that accept detachable magazines, part of a firearms package approved by state lawmakers in response to mass shootings in other states.

It was lawmakers' latest attempt to close loopholes that have allowed manufacturers to work around previous assault weapon bans. Gun rights groups had threatened to sue if the semi-automatic weapons ban became law.

"I don't believe that this bill's blanket ban on semi-automatic rifles would reduce criminal activity or enhance public safety enough to warrant this infringement on gun owners' rights," the Democratic governor wrote in his veto message.

He also noted that California already has some of the nation's strictest gun and ammunition laws.

Democratic Senate President Pro Tem Darrell Steinberg, who proposed the measure, did not immediately respond to requests for comment.

The bill sought to ban the sale of assault rifles, but Brown objected that it also would have applied to low-capacity weapons commonly used for hunting, firearms training and target shooting, and some historical and collectible firearms. Brown also didn't want thousands of legal gun owners to have to register their existing weapons as assault rifles and be blocked from selling or transferring the weapons.

The governor's actions were a mixed bag for both gun rights groups and those seeking greater restrictions.

He signed a measure from Assemblywoman Nancy Skinner, D-Berkeley, which bans kits that allow people to turn regular ammunition magazines into high-capacity magazines, as well as two other pieces of legislation that restrict the ability of mentally ill people to possess firearms.

Brown approved a measure making California the first state to impose a statewide ban on lead bullets for all types of hunting. Hunting with lead bullets already is prohibited in eight counties with endangered California condors. About two dozen states also have partial bans, most in sensitive wildlife refuges.

But he vetoed other bills including measures giving several San Francisco-area communities special authority to regulate weapons and gun shows, as well as several other bills he said went too far to restrict the sale or possession of certain types of handguns or shotguns.

Some of the new laws could trigger legal challenges.

Gun owners' rights groups have said they also could consider mounting recall campaigns or election-year challenges against Democratic lawmakers who voted for the gun bills. Final votes on the legislation occurred last month, just as two Colorado state lawmakers were recalled for supporting tougher gun laws in that state.